/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated January 1, 2020. Replaces all prior versions.
 *
 * Copyright (c) 2013-2020, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
 * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using UnityEditor;
using UnityEngine;
using Spine.Unity.Examples;

namespace Spine.Unity.Editor {
    // This script is not intended for use with code. See spine-unity documentation page for additional information.
    [CustomEditor(typeof(SkeletonGraphicCustomMaterials))]
    public class SkeletonGraphicCustomMaterialsInspector : UnityEditor.Editor {
        List<SkeletonGraphicCustomMaterials.AtlasMaterialOverride> componentCustomMaterialOverrides, _customMaterialOverridesPrev;
        List<SkeletonGraphicCustomMaterials.AtlasTextureOverride> componentCustomTextureOverrides, _customTextureOverridesPrev;
        SkeletonGraphicCustomMaterials component;

        const BindingFlags PrivateInstance = BindingFlags.Instance | BindingFlags.NonPublic;
        MethodInfo RemoveCustomMaterialOverrides, RemoveCustomTextureOverrides, SetCustomMaterialOverrides, SetCustomTextureOverrides;

        #region SkeletonGraphic context menu
        [MenuItem("CONTEXT/SkeletonGraphic/Add Basic Serialized Custom Materials")]
        static void AddSkeletonGraphicCustomMaterials(MenuCommand menuCommand) {
            var skeletonGraphic = (SkeletonGraphic)menuCommand.context;
            var newComponent = skeletonGraphic.gameObject.AddComponent<SkeletonGraphicCustomMaterials>();
            Undo.RegisterCreatedObjectUndo(newComponent, "Add Basic Serialized Custom Materials");
        }

        [MenuItem("CONTEXT/SkeletonGraphic/Add Basic Serialized Custom Materials", true)]
        static bool AddSkeletonGraphicCustomMaterials_Validate(MenuCommand menuCommand) {
            var skeletonGraphic = (SkeletonGraphic)menuCommand.context;
            return (skeletonGraphic.GetComponent<SkeletonGraphicCustomMaterials>() == null);
        }
        #endregion

        void OnEnable() {
            Type cm = typeof(SkeletonGraphicCustomMaterials);
            RemoveCustomMaterialOverrides = cm.GetMethod("RemoveCustomMaterialOverrides", PrivateInstance);
            RemoveCustomTextureOverrides = cm.GetMethod("RemoveCustomTextureOverrides", PrivateInstance);
            SetCustomMaterialOverrides = cm.GetMethod("SetCustomMaterialOverrides", PrivateInstance);
            SetCustomTextureOverrides = cm.GetMethod("SetCustomTextureOverrides", PrivateInstance);
        }

        public override void OnInspectorGUI() {
            component = (SkeletonGraphicCustomMaterials)target;
            var skeletonGraphic = component.skeletonGraphic;

            // Draw the default inspector
            DrawDefaultInspector();

            if (serializedObject.isEditingMultipleObjects)
                return;

            if (componentCustomMaterialOverrides == null) {
                Type cm = typeof(SkeletonGraphicCustomMaterials);
                componentCustomMaterialOverrides = cm.GetField("customMaterialOverrides", PrivateInstance).GetValue(component) as List<SkeletonGraphicCustomMaterials.AtlasMaterialOverride>;
                componentCustomTextureOverrides = cm.GetField("customTextureOverrides", PrivateInstance).GetValue(component) as List<SkeletonGraphicCustomMaterials.AtlasTextureOverride>;
                if (componentCustomMaterialOverrides == null) {
                    Debug.Log("Reflection failed.");
                    return;
                }
            }

            // Fill with current values at start
            if (_customMaterialOverridesPrev == null || _customTextureOverridesPrev == null) {
                _customMaterialOverridesPrev = CopyList(componentCustomMaterialOverrides);
                _customTextureOverridesPrev = CopyList(componentCustomTextureOverrides);
            }

            // Compare new values with saved. If change is detected:
            // store new values, restore old values, remove overrides, restore new values, restore overrides.

            // 1. Store new values
            var customMaterialOverridesNew = CopyList(componentCustomMaterialOverrides);
            var customTextureOverridesNew = CopyList(componentCustomTextureOverrides);

            // Detect changes
            if (!_customMaterialOverridesPrev.SequenceEqual(customMaterialOverridesNew) || !_customTextureOverridesPrev.SequenceEqual(customTextureOverridesNew)) {
                // 2. Restore old values
                componentCustomMaterialOverrides.Clear();
                componentCustomTextureOverrides.Clear();
                componentCustomMaterialOverrides.AddRange(_customMaterialOverridesPrev);
                componentCustomTextureOverrides.AddRange(_customTextureOverridesPrev);

                // 3. Remove overrides
                RemoveCustomMaterials();

                // 4. Restore new values
                componentCustomMaterialOverrides.Clear();
                componentCustomTextureOverrides.Clear();
                componentCustomMaterialOverrides.AddRange(customMaterialOverridesNew);
                componentCustomTextureOverrides.AddRange(customTextureOverridesNew);

                // 5. Restore overrides
                SetCustomMaterials();

                if (skeletonGraphic != null)
                    skeletonGraphic.LateUpdate();
            }

            _customMaterialOverridesPrev = CopyList(componentCustomMaterialOverrides);
            _customTextureOverridesPrev = CopyList(componentCustomTextureOverrides);

            if (SpineInspectorUtility.LargeCenteredButton(SpineInspectorUtility.TempContent("Clear and Reapply Changes", tooltip: "Removes all non-serialized overrides in the SkeletonGraphic and reapplies the overrides on this component."))) {
                if (skeletonGraphic != null) {
                    skeletonGraphic.CustomMaterialOverride.Clear();
                    skeletonGraphic.CustomTextureOverride.Clear();
                    RemoveCustomMaterials();
                    SetCustomMaterials();
                    skeletonGraphic.LateUpdate();
                }
            }
        }

        void RemoveCustomMaterials() {
            RemoveCustomMaterialOverrides.Invoke(component, null);
            RemoveCustomTextureOverrides.Invoke(component, null);
        }

        void SetCustomMaterials() {
            SetCustomMaterialOverrides.Invoke(component, null);
            SetCustomTextureOverrides.Invoke(component, null);
        }

        static List<T> CopyList<T>(List<T> list) {
            return list.GetRange(0, list.Count);
        }
    }
}
